The plane went down in thick woods east of Blue Ridge Lake, just missing a home, Major Keith Bosen, of the Fannin County Sheriff's Department, told the AJC.
Searchers quickly found three bodies, but as of 11 p.m. had not found the fourth person who was aboard the plane, Bosen said. No one on the ground was hurt.
Bosen said the plane flew about 100 feet over a house on Star Creek Road near Morganton in Fannin County, before it crashed. The resident called the sheriff at 4:26 p.m., he said.
The aircraft was a US Navy T-39 Sabreliner assigned to a training squadron based in Pensacola, according to the Pensacola News Journal, which quoted a Navy spokesman.
It's unclear why the aircraft was flying in the area, but Bosen, a former Marine maintenance officer, said Blue Ridge is in the flight path for military training exercises. He said several local officers reported seeing the aircraft flying noticeably low earlier in the day.
The crash occurred in a densely-wooded section of forest without trails, making the scene difficult to access.
The impact left the aircraft in pieces and started a fire that consumed as many as 15 acres. U.S. Forest Service firefighters battled the blaze with help from local firefighters and two helicopters that were dumping water. By 11 p.m., Bosen said, the fire was contained and was expected to go out after it burned what remained within a perimeter created by firefighters.
Bosen said local authorities would secure the crash scene overnight until Navy investigators, who were expected to arrive in the morning, could take over and resume the search for the fourth person. "At this point, it's too dark for us to do anything whatsoever," he said.

Heard about that on WSB this morning. Sad to hear. They do a lot of training exercises over my house. I live right by the cherokee county airport and apparently its the first airport north of the city that they are able to do exercises.

I would imagine those guy were probably doing some sort of training exercise.